De-intensification of Radiation and Chemotherapy for Low-Risk HPV-related Oropharyngeal SCC: Follow-up Study

The proposed study is a follow-up study to NCT01530997. In NCT01530997, patients with HPV positive and/or p16 positive low-risk oropharyngeal squamous cell carcinoma (OPSCC) received de-intensified chemoradiotherapy (CRT) followed by a limited surgical evaluation. The primary endpoint of NCT01530997 was the rate of pathological complete response (pCR) after CRT. Power computations were performed for N=40 and were based on the null hypothesis (H0) that the pCR for de-intensified chemoradiotherapy is at least 87%, the historical rate. The type 1 error for this calculation was 14.2%. 43 patients enrolled and 38 were evaluable for the primary endpoint. The observed pCR rate was 89% (34/38). Since the observed pCR rate was excellent in NCT01530997 and was in concordance with the expected rate, in the proposed study we will not mandate a post-CRT surgical evaluation. Instead a PET/CT 10 to 16 weeks post-CRT will be used to determine whether a surgical evaluation is needed.

Inclusion criteria

• ≥ 18 years of age (no upper age limit)
• T0-3, N0 to N2c, M0 squamous cell carcinoma of the oropharynx
• Biopsy proven squamous cell carcinoma that is HPV and/or p16 positive
• ≤ 10 pack-years smoking history or ≤ 30 pack-years smoking history WITH ≥ 5 years abstinence from smoking
• Radiologic confirmation of the absence of hematogenous metastasis within 12 weeks prior to treatment
• ECOG Performance Status 0-1
• CBC/differential obtained within 8 weeks prior to treatment, with adequate bone marrow function defined as follows: Platelets ≥ 100,000 cells/mm3; Hemoglobin ≥ 8.0 g/dl.
• Adequate renal and hepatic function within 4 weeks prior to registration, defined as follows: Serum creatinine < 2.0 mg/dl; Total bilirubin < 2 x the institutional ULN; AST or ALT < 3 x the institutional ULN.
• Negative serum pregnancy test within 2 weeks prior to registration for women of childbearing potential
• Women of childbearing potential and male participants who are sexually active must practice adequate contraception during treatment and for 6 weeks following treatment.
• Patients must be deemed able to comply with the treatment plan and follow-up schedule.
• Patients must provide study specific informed consent prior to study entry

Exclusion criteria

• Prior history of radiation therapy to the head and neck
• Prior history of head and neck cancer.
• Unresectable disease (e.g. immobile node on physical exam, nodal disease that radiographically involves the carotid arteries, nerves)
• Currently taking Disease Modifying Rheumatoid Drugs (DMRDs)
• Severe, active co-morbidity, defined as follows: Unstable angina and/or congestive heart failure requiring hospitalization within the last 6 months; Transmural myocardial infarction within the last 6 months; Acute bacterial or fungal infection requiring intravenous antibiotics at the time of registration; Chronic Obstructive Pulmonary Disease exacerbation or other respiratory illness requiring hospitalization or precluding study therapy at the time of registration; Hepatic insufficiency resulting in clinical jaundice and/or coagulation defects (Note, however, coagulation parameters are not required for entry into this protocol); Pre-existing ≥ grade 2 neuropathy; Prior organ transplant; Systemic lupus; Psoriatic arthritis.
• Known HIV positive.